Researchers at the University of Southern California have tracked every cancer diagnosis in Los Angeles — more than 1.3 million — for nearly 40 years. And the result of those four decades of research, a new report called Cancer in Los Angeles County: Trends by Race/Ethnicity 1976-2012, has produced extraordinary insight into the disease. While there is, sadly, still no cure, the data show that prevention can often be a simple matter of diet and avoiding bad habits.

"The majority of cancer in Los Angeles is preventable," said Keck School of Medicine professor Dennis Deapen, the report’s senior author. "You can reduce the risk yourself. Let this be a reminder to get appropriate checkups to help identify any cancer early."

For example, the report highlights the difference in breast cancer rates between Asian-American women and those who live in Asian countries.

"Asian women living in Los Angeles experience higher and continuously rising breast cancer risk compared to their counterparts living in Asia," USC said in a statement. "That’s because breast cancer is more prevalent in developed countries with Westernized lifestyles."

At the same time, immigrants in Los Angeles tend to see a decrease in cancers that are more prevalent in their home countries.

"The general explanation is the exposures to risk factors associated with specific infections and lifestyle choices change once immigrants leave their home country," said lead author Lihua Liu, also a USC Keck School professor. "For example, the prevalence of H. pylori [a digestive bacteria] and HBV [hepatitis B] infections is much lower in the U.S. than in Asian countries. Both are major risk factors for stomach and liver cancers, respectively."

Los Angeles, home to nearly one in 10 of the nation's Latinos and Asian-Americans, proved to be a great lab for researchers looking to figure out how diet and lifestyle can affect people.

"The message for immigrant populations is very clear," Liu said. “When they come to this country, their lifestyle changes affect their cancer risk."

Black men have the highest rates of cancer in L.A., the study found. And lung cancer is the top form of cancer for men of Vietnamese descent, it found. Breast and colorectal cancer are the most prevalent cancers for L.A. women. Meanwhile, skin cancer is on the rise, especially for white residents, the research found.

The good news is that there's been a "steady decline in the overall rate of deaths due to cancer," Deapen said.

USC

Dennis Romero has worked on staff at several magazines and newspapers, including the Philadelphia Inquirer and the Los Angeles Times, where he participated in Pulitzer Prize-winning coverage of the L.A. riots. His work has appeared in Rolling Stone online, the Guardian, and, as a
young stringer, the New York Times.